Atlas V rocket carries missile-detecting satellite into orbit

On 7 May, a United Launch Alliance Atlas V rocket carried
the next generation of a satellite designed to detect missile
launches into orbit.

After a rocky start and a delayed launch, the Atlas V
blasted off from Cape Canaveral Air Force station on Saturday
morning, hauling the $1.2 billion (£730m) SBIRS GEO-1 satellite
into space.

The GEO-1 is just one soldier in an army of satellites
planned to launch into geostationary orbit throughout 2011.
Together they form SBIRS (or Space-Based Infra-Red System), which
use infrared sensors to detect and track missile launches from
around the globe.

The US military considers the SBIRS program one of its most
high priority space programs at the moment. Reconnaissance
satellites were given a big pat on the back this month when a fleet
of navigation, communications and imaging probes helped flush out
Osama bin Laden.

But the current collection of satellites in use just aren't
quite up to snuff when dealing with the threats of 2011. The new
GEO-1 satellite will take over from creaky old missile-warning
systems, some of which are leftovers from the Cold
War.

Missile-warning satellites go back to the 1960s. The MIDAS
(or Missile Defense Alarm System) was a system of low Earth orbit
satellites -- equipped with infrared sensors -- that went up
throughout the 60s. The Midas 7, which launched 48 years ago (9
May, 1963), detected the first ever missile launch from space.

After dodgy launches and shoddy power supplies, the
satellites were deemed obsolete within a few years and the MIDAS
program was scrapped. In the 70s it was replaced with DSP (or
Defense Support Program).

These new reconnaissance satellites would orbit the Earth
from ten times the altitude of MIDAS (floating about in
geostationary orbit, meaning they remain above the same spot on the
Earth's surface, rather than low Earth orbit),
providing the military with a constant view of the entire planet's
infrared activity. The 23 satellites proved so successful that most
of them are still up there now.

But the SBRIS system is a big
upgrade. The satellite's sensor is rather faster, allowing it
to look at one location and then gaze at another rapidly. It's also
more sensitive than DSP, and its revisit time is significantly
shorter. With SBRIS, raw, unprocessed data can be downloaded to
stations on the ground, so the globe's radiometric scene can be
observed in real time from Earth.

The system will provide the US with critical missile defense
and warning capability well into the 21st century, as well as
technical intelligence and battle-space awareness.